Performing research on the Android Market

There are various out there that can help perform a research on Android applications.

1. Android Market application
2. Android Market web site - Has difference number of downloads scale. While the highest value in the Market application is >250K, in the web site there are different values: 50K-100K, 100K-500K, 500K-1M, 1M-5M, 5M-10M, 10M-50M
3. AndroLib - Has application rating (stars) history
4. AndroidZoom - Has application history: release dates & events (when the application passed a download group (e.g. 10K-50K, 50K-250K).
5. AppAnnie - Market analytics (alternatives: Android App Tracker - Has application market ranking history, AndroidRanking.com - Another Android market tracking site).

If you have more interesting sites, please share.

Update Jan-2013: VisionMobile just lunched a great site for developers called Developer Economics that contain a tools atlas with all the tools that can help the developer.